函数不返回值，因此实际上是在擦除现有状态。

此外，这个钩子将当前的post作为对象传递给您，因此您可以使用它来代替全局$post。

另外get_page_templ‌​ate_slug 返回相对于主题根的路径，因此如果调用主题目录Lef-en-Liefde 位于该目录顶层的模板文件称为woningoverzicht.php, 那么你的情况\'/themes/Lef-en-Liefde/woningoverzicht.php\' == get_page_templ‌​ate_slug($post->ID) 不可能是真的。

因此，针对这些点进行纠正/更改时，应该可以：

add_filter(\'display_post_states\', \'wpse240081_custom_post_states\',10,2);

function wpse240081_custom_post_states( $states, $post ) { 
    
    if ( ( \'page\' == get_post_type( $post->ID ) ) 
        && ( \'woningoverzicht.php\' == get_page_templ‌​ate_slug( $post->ID ) ) ) {

            $states[] = __(\'Custom state\'); 

    } 

    return $states;
} 

WooCommerce是如何做到这一点的：

<?php
add_filter( \'display_post_states\', \'add_display_post_states\', 10, 2 );

/**
 * Add a post display state for special WC pages in the page list table.
 *
 * @param array   $post_states An array of post display states.
 * @param WP_Post $post        The current post object.
 */
function add_display_post_states( $post_states, $post ) {
    if ( wc_get_page_id( \'shop\' ) === $post->ID ) {
        $post_states[\'wc_page_for_shop\'] = __( \'Shop Page\', \'woocommerce\' );
    }

    if ( wc_get_page_id( \'cart\' ) === $post->ID ) {
        $post_states[\'wc_page_for_cart\'] = __( \'Cart Page\', \'woocommerce\' );
    }

    if ( wc_get_page_id( \'checkout\' ) === $post->ID ) {
        $post_states[\'wc_page_for_checkout\'] = __( \'Checkout Page\', \'woocommerce\' );
    }

    if ( wc_get_page_id( \'myaccount\' ) === $post->ID ) {
        $post_states[\'wc_page_for_myaccount\'] = __( \'My Account Page\', \'woocommerce\' );
    }

    if ( wc_get_page_id( \'terms\' ) === $post->ID ) {
        $post_states[\'wc_page_for_terms\'] = __( \'Terms and Conditions Page\', \'woocommerce\' );
    }

    return $post_states;
}

如果在自定义插件中使用该过滤器，则需要使用函数；get\\u post\\u meta“获取”；因为函数；get\\u page\\u templ‌​ate\\U slug“；尚未加载

示例：

add_filter(\'display_post_states\', \'wpse240081_custom_post_states\', 10, 2);

function wpse240081_custom_post_states( $states, $post ) {
    
    // if is list page and name template file php...
    if ( ( \'page\' == get_post_type( $post->ID ) ) && ( \'your-template-name.php\' == get_post_meta( $post->ID, \'_wp_page_template\', true ) ) ) {

        $states[] = __(\'Custom state\');
    }

    return $states;
}